Nobody every actually believed the i3 would last longer, since even in "heavy" use presented above the i5 is in idle for 5-8ms out of every 15ms frame. If the i3 draws half as much power in max but spends twice as much time there, battery life won't change much. Not to mention the display draws the most power during idle, so the CPU specs are watered down a bit there.Reply

Chrome fixed the CPU tick issues (which have been present since v1), causing major battery life problems in the latest Canary build. We're talking 25% less drain, based on a prediction by MS a few years back. Since idle power use has dropped by a very considerable amount in the past couple years on Intel platforms, I wouldn't be surprised if that number is now closer to 35%-40%.

It's still considerably slower than I.E. or Firefox, but the featureset keeps a lot of users. Including myself, lol.Reply

Deactivating Turbo on low-TDP parts is a particularly bad idea, as you're robbing yourself of significant single-thread performance gains. A far better option would be to leave turbo active but to lower the power consumption limit / target (if you feel a need to do so).Reply

I'm struggling to understand how it can only have 37GB of free space. Even with the recovery partition, I still have enough space to install a game or two on my 32GB Dell Venue 8 Pro. I wouldn't expect there to be crapware on a Surface, so what is taking up all the space?Reply

I've done quite a bit of Xen power tuning recently, and I'm not surprised by this at all. The reduced cache size on the i3 means that the same operations take the system out of C7 for much longer than on an i5. Long enough to overcome the wattage difference. If you look at your package C-state residency, I think you'll find the answer has less to do with binning than you think.

So you get worse performance and worse "idle" battery life. But at least it's cheaper....Reply

The architectural strategy of "Hurry up and wait" is often the most energy-efficient. Run the chip at its optimal power*performance point, and then shut it off. This is why your cell phones, even, ramp up the clock speed when doing something, then put it to sleep. Both dynamic switching power and gate leakage power are saved when clock/power gating during sleep modes.

Of course, quite a few people don't realize this, and customize their kernel to reduce maximum clock speed and such - thinking that this conserves battery. Kind of like undervolting on a smartphone - you may get a couple minutes of extra battery life, but certainly not worth the potential loss in stability.Reply

The most important metric in such tests however is the amount of work must be fixed relative to the battery power the device has. Tasks finishing faster mean you have more time to do more tasks, and thus battery life can be "shorter".Reply

I often wondered this on any battery life test. Device A might get worse battery life than Device B, but if the given test is a loop, then what happens if Device A made it through the loop more times? There's battery life in terms of time till dead, and then there's amount of work potential in a charge. The i5 Surface may have more work potential per charge, but the i3 Surface can last longer if the demand is light. Reply

That's right. I'll play Minecraft on battery power every once in a while, and it lasts significantly longer when it's on low-power mode.

Actually, running it at 700 MHz constantly makes it last longer than if it was going full-bore, even when it's not doing much. Race-to-sleep sounds like it should be working better, but I haven't noticed it. Running the CPU at full while sitting idle on the desktop increases my power usage from 6 or 7 watts to 9 or 10 watts.Reply

i lost all desire on surface 3 after the tear-down showed that it is even more impossible to replace battery on surface 3 than on the previous king on planned obsolescence ipad. This battery is expected to fail after 2-3y, and any attempt to replace it will destroy the display. we definitively need a regulation forbidding companies to deploy products with impossible to replace and doomed to fail batteries. Reply

Plus the lack of usable ports. Common Microsoft, one USB port (Ok, understandable), one mini freaking display port (Yeah, again, I understand, 4K, older HDMI standards, blah blah), and a MICRO freaking SD slot ( What were you smoking?) in a device that is targeted at photo professionals?. And why does the 64GB version even exist?! Isn't it like just a $40 difference for a 128GB?

Seriously, I have been a big fan of the device right from the first Gen and have been advocating it since, but then I realised I would never buy one due to the limitations mentioned above.Reply

"Targeting photo professionals" and "$40 difference for 128GB model". So obviously you make up your own facts and marketing material because neither of those has ever been the case. Yea big draw back on only ONE mini display port...lol because we all NEED more than one on a tablet of all devices... And yea that mini SD slot... wow what a let down, I can add 50% more storage to my 128GB Pro for $25, woe is me. Not sure also where the guy above you got a 2-3 year battery life, I've had the Pro gen 1 since day one, used it every day through 2 years of college and still holds the same charge as it always has. Not to mention, I haven't seen anything that would suggest anything close to a wide spread battery failure on all of the original release Pro's. It is always fun to read the anti-Surface people's ridiculous complaints though.Reply

These are not using LiON batteries, they are using LiPo batteries. The usable lifespan before degradation is significantly longer, expect 4-5 years or so. We have an iPad at work, first generation, its battery life is still very good, even after all the iOS updates and heavy usage for testing. My original Kindle Fire still gets a solid 6+ hours.

LiPo is one of the major reasons we moved to sealed battery designs. Replacing the battery is no longer a necessary scenario with the exception of people who keep charged spares. By the time the battery is unusable, the device will be reasonably obsolete.Reply

And on the topic of charged spares, the Power Cover is working well for me (with the weird exception that I don't like taking the cover off to use it in 'tablet mode' anymore, because then I'll be using up my main battery).Reply

I swapped my i5/256 for i7/256 on August 1, and so far my tests indicate slight performance increase (around 5-10% depending on the test), while battery life seems to be about the same as i5 model. I tried playing a game World of Tanks on it just to see how long would it last, and I got somewhere between 3 and 3.5 hours (I didn't time it to be precise, just to get a ballpark estimate) until Windows showed me a warning that the charge is 10%. At work (mostly Visual Studio 2013, Office suite) I got about 6.5 hrs (compilation is very CPU-intensive, but relatively short, and TurboBoost totally excels in this scenario), including about 40 minutes of using OneNote in the meeting for note-taking. This is good enough for me (especially since I'm getting a dock so battery life will become a non-issue at work). One thing I've noticed is that I use the device at home more like a cell phone, than a laptop - namely I use it unplugged, and charge it when not in use.Reply

I already said I had brightness set to almost as dim as possible. I do use Chrome sometimes but it seems to be the same in both browsers. I will try IE when I can. I have 2 sites that for some reason don't work in anything but chrome.Reply

No, Microsoft only provided the Core i5 for reviews, which I think makes sense. Having said that, I did pick up a Core i7 (personal) this weekend, even traded in a MBA for it to see how that went. I plan on doing a follow up review with the Core i7, though I cannot promise to meet AnandTech's rigid benchmarking/performance analysis. I tend to write more as a regular consumer, only because I know my limiters on these types of articles.

I think though people's gut instincts about the different Core options vs. Performance/battery life are pretty spot on so far. There really are no surprises. Will see how it goes in a few more days.Reply

Were these tests done with Google Chrome? The intentional CPU pinging has not been fixed and is still an issue even with the newer kernel of Windows 8. It would be very...troubling to thing that even after the recent public attention this issue received that battery tests would still be done with it.Reply

Chrome sucks big time on SP3 in "desktop" mode (HiDPI support is buggy), and it didn't work for me at all when I tried to run it in "Metro" mode - just got a grey screen and no reaction to whatever I do (well except for system gestures of course). Which forced me - long time Chrome user in both Windows and Android's tablets/phones - to move to IE11.Reply

So, assume I am really out to lunch about the battery thing? What does these numbers mean? I bought a surface pro 3 and sold my Dell Venue 11 pro and am now a bit upset I did. I wanted the i5 and 8gb and 256 ssd, however, my battery lasts for crud. I am lucky if I get 4 hours, I am not even doing anything hard to it either. This is just when playing a casual game like diner dash or a facebook flash game. This is my second Surface Pro 3, I returned the first one due to it being un bearably hot and short battery life. I love the machine but am upset. How do I tune it better? I already have the screen super dim. Will a firmware update help this. Makes it almost useless to me as a work device so I haven't even brought it in to try yet.Reply

Yes, I try to do updates and it doesn't find anymore so as far as I know it does. This is my second Surface Pro 3... They can't all be messed up but I can't figure out what the deal is. Even when I do powercfg /batteryreport it reports a max of 4.5 hours for the estimate (which I have yet to get) I called Microsoft numerous times. They keep telling me its my apps and to reset the machine again, this is how I ended up exchanging the first one, the store tells me they get 9 hours.... grrrrr if anyone has any pointers or what I should be looking for I sure would appreciate it I can't figure out what I am doing wrong.Reply

You are getting the correct battery life. There's nothing wrong with your computer. Flash games will eat up your battery. Nothing you can do about it that's the reality of the technology. The 7-8 hours of battery life is when you are web browsing like shopping and reading a news article. Reply

Also, you are basically talking about worst-case scenario battery life if you want to play flash games - flash sucks (the life out of batteries). Actually, games in general are a good way to suck the life out of your device. The latest iPhone for example, which one could probably squeeze out to about two days will be flat in 3-4 hours of gaming.Reply

Yeah, there's no such thing as 'only' playing a game. Games run a constant loop, so they generally use up all the CPU power they can -- especially Flash. Getting 4 hours on a game on a windows laptop is actually really impressive. A few years ago, you'd be lucky to get half that.

Here's something you can do: Click on the battery icon in the notification area, and open More Power Options. You can "Change plan settings" next to the Power Saver plan, and then "Change advanced settings" to open a dialog box of options. Go through that and make sure everything is set to be maximally power-saving on battery. Set the Minimum and Maximum processor state to something low, like 1% or whatever. It has its own minimum level. If your games get choppy and laggy, set the maximum state to 50% or something. Add salt to taste.Reply

I was using Chrome because I have a school website that only works right in Chrome. But last night I tried to use IE as much as possible and it seemed to do a bit better. I had no idea a flash gameo n facebook was such a battery hog. I wish that wasn't the case. Thanks for the tip! I hope they make the power cover for the Pro 3.Reply

I really can't imagine it. The power cover is about as thick as the Surface itself, and this latest update is all about thinness. I laid my bare Surface Pro 1 next to a friend's Surface Pro 3 with its Type Cover, and they were about the same thickness.

Power Cover is good for me, because I'd only get maybe 4 or 5 hours out of it otherwise, but Surface Pro 3 is efficient enough that runs as if it already includes Power Cover.

(I could see them introducing some ultra-slim external battery cover, which might give you an extra two hours or so. Unless they actually come out with a thick expansion-dock cover with a battery and extra ports, which would be fantastic. Who knows!)Reply

Both of those programs have far better CPU management (don't fuss with timers at all, Word doesn't even refresh the window unless you do something), so they are basically idle scenarios. I'm sure it gets in the 9hr range just fine.

As for fullhd from file rather than wifi, it'll have better life because there's no wifi, but doubtful it will budge much unless you either change the file (h264 complexity, and therefore computation time, varies wildly between sources and even when bitrates and internal parameters change) or have extremely low wifi signal (which results in a power consumption increase between upped gains and packet loss)Reply

Does microsoft delete your reviews? I bought one i5 and one i7 and wrote reviews for both and confirmed it, but they are not showing up on their site. I've had nothing but trouble with the i7.

First i7 256gb had noticeable backlight bleed in all the corners.Second one had severe bleed on top rightNow the third one cant update the firmware update. I get a dreaded thermometer symbol and the machine turns off by itself in the middle of the update. Refreshed the machine and the same thing…Dreading going back for a 4th machine.Reply

The Surface Pro 3, particularly with the i5/i7 gets hot as f#*k, and must be baby'ed to a degree because it has something the ARM tablets don't. A FAN. This is huge deal when choosing between a i3 Surface and a. say, Elitepad 1000 or another tablet.Reply